Nondestructive evaluation of carbon fibre reinforced composites with infrared thermography and ultrasonics

Post-processing of time-sequences acquired during impact tests with the aid of a reference area

“…This feature may seem simple to perform, but it represents a crucial task because of problems, linked to the different behaviours of materials under impact and to the instrument noise, which render difficult a generalization. In particular, thermoset matrix based composites become damaged on the side opposite to that struck by the impactor, often without any visible perception on the impacted side, or with only barely visible indentation [12]. Composites including a thermoplastic matrix behaves in a different manner under impact; in fact, they undergo visible deformation displaying an indentation (a small concavity) on the impacted side and a protrusion on the rear one [13].…”

“…1 allows the infrared camera to view the surface opposite to the impact. The specimen is positioned inside a specific lodge, which is made of two large plates, each having a window to allow for the contact with the hammer head from one side and optical view (by the infrared camera) from the other one [12]. A reference specimen is used for correction of the detector noise.…”

Detection and characterisation of delamination damage propagation in Woven Glass Fibre Reinforced Polymer Composite using thermoelastic response mapping

“…The primary attraction of thermographic techniques is that they furnish full-field imagery and thereby are generally much more rapid than point-wise alternatives such as conventional ultrasonics and tap testing. A number of different variants have been successfully applied to composite inspection, including pulsed thermography (Liang et al 2016), lock-in thermography (Junyan et al 2015) and sonic thermography (Kuhn, Valot & Herve 2012;Meola et al 2015). While thermoelastic stress analysis (TSA) is seldom categorised as a non-destructive inspection tool it has the capacity to be used in that role quite effectively.…”

Characterisation of artificial defects in CFRP and GFRP sheets designed for energy applications using active thermography

“…The thermographic inspection of CFRP and GFRP test specimens during tensile loading or impact damage can provide information about the types of damage already during the damaging process [2][3][4][5]. In [3], thermography was combined with acoustic emission for the investigation of static load in unidirectional carbon fibres laminates subjected to axis and off-axis static tensile loads.…”